function s1_goto_dir(){
 cd "$1"
}
function s2_touch_empty_file_with_given_name(){
 touch "$1"
}
function s3_make_directories(){
 mkdir -p projects/{git,backup}
}
function s4_create_6_files(){
 touch projects/{liunx1,liunx2}_{centos,redhat,c_programming}
}
function s5_make_directories_in_git(){
 mkdir -p projects/git/{linux1,liunx2}
}
function s6_move_files_to_dir_1_or_2(){
 mv projects/git/liunx1 projects/liunx1_* && mv projrcts/git/liunx2 projects/liunx2_*
}
function s7_create_package_and_compress(){
 tar -czvf projects/backup/git.tar.gz projects/git
}
function s8_delete_dir_git(){
 rm -rf projects/git
}
function s9_recover_from_git_tar_gz_backup(){
 tar -czvf projrcts/backup/git.tar.gz
}
function s10_create_packup_and_compress(){
 tar -czvf projects/backup/git.tar.bz2 projects/git
}
function s11_find_and_sort_alphabetically_all_created_files_and_dirs(){
 find ./projects |sort
}
function s12_get_next_15_minutes_boundary(){
date + '%Y-%m-%d_%H:%M:%S'-d @$(( $(date+%s)/900*900+899))
}

 
